Mining machine windrow shield



Oct. 28, 1969 N. E. EVANS MINING MACHINE WIN'DROW SHIELD 2 Sheets-Sheet 1 Flled Sept 26, 1967 INVENTOR.

NOLAN E. EVANS Oct. 28, 1969 2 Sheets-Sheet 2 Filed Sept. 26, 1967 INVENTOR.

NOLAN E. EVANS United States Patent US. Cl. 299-57 5 Claims ABSTRACT OF THE DISCLOSURE A mining machine having ground-engaging tracks supporting a sub-frame. The sub-frame supports a main frame having a gear case and a motor. Boring shafts journaled in the gear case extending lengthwise of the sub-frame and spaced apart transversely of the sub-frame. The boring shafts having radially disposed cutter arms secured to the forward ends of the boring shafts. Permanently secured to at least one side of the gear case are shielding means having a vertical shield wall adapted to be placed in a forward shielding position adjacent one boring shaft and spaced therefrom a greater distance than the length of the cutter arms. The shield wall in the forward shielding position extends further forward than the cutter arms and extends from near ground level to about the level of the boring shaft. In this position, particles of the material being mined which tend to move horizontally transversely away from the machine, contact the shield wall and are deflected downward for movement to a conveyor. Locking means are provided to secure the shield wall in the forward shielding position. Support means which are rotata-bly secured to both the gear case and the shield wall are also provided. The shield wall may be moved to a rear storage position, when not in use.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to mining machines having shielding means for preventing the creation of windrows adjacent the machines during multi-pass mining operations. More specifically, this invention relates to mining machines having rotary boring shafts with radially disposed cutter arms and having a permanently secured windrow shield adapted to assume either a shielding position or a storage position.

Description of the prior art Among the many known types of continuous mining machines is a boring type mining machine generally designated as the McKinley entry driver. This type of machine has continuous ground-engaging treads which facilitate progressive movement of the mining machine into the seam, as the material being mined is removed. A subframe is supported on the ground-engaging treads and it in turn supports a main frame having a gear case. Boring shafts journaled in the gear case, extend lengthwise of the sub-frame and out of the forward end of the gear case. The boring shafts are spaced apart transversely of the subframe and each shaft has several radially disposed cutter arms. As the boring shafts rotate, the material being mined is dislodged from the mine face and falls to the floor of the seam. Continued rotation of the cutter arms causes pusher plates disposed at the leading edge of the cutter arms to move the material on the ground toward the transverse center of the mining machine. A conveyor disposed lengthwise of the sub-frame communicates with the front of the machine at the transverse center. The material is picked up on the conveyor and carried upwardly and rearwardly to a position behind the machine. Such machines 3,475,057 Patented Oct. 28, 1969 ice have long been known and are described in United States Patents 3,294,450 and 3,309,143.

As the cutting path of the cutters mounted 0n the two boring shafts is generally similar to two overlapping circles, triangular cusps remain at the top and bottom in or around the transverse center of the machine. These machines therefore, are provided with top and bottom trimmer bars which have cutter chain guides through which an endless cutter chain passes. This endless cutter chain severs the upper and lower cusps. The machine thus provides a cut which is similar to an ellipse.

When this equipment is employed in single-pass mining, the machine moves in a single narrow passageway or seam. The machine is therefore, moving in a passageway having sidewalls closely adjacent each side of the machine. Any pieces of material moving horizontally transversely outwardly of either side of the machine, will hit the side walls and drop downwardly to the passageway floor. The pieces will then be moved transversely inwardly toward the conveyor, by means of the cutting arms which have pusher plates attached to their leading edges for this purpose. This is not the case in multi-pass mining, however. In multi-pass mining, after an initial passageway is created, the machine is withdrawn and a second passageway which partially overlaps the first is established. The second pass almost doubles the width of the initial passageway. Each subsequent pass is accomplished in similar fashion with the machine having one side adjacent the previously opened passageway and the other side adjacent a sidewall of the material being mined.

In multi-pass mining, after the initial pass, particles of the material moving transversely out of the side of the machine adjacent the previously established passageway continue to move in a generally horizontal path into the previously formed passageway. Unlike single pass mining, there is no physical barrier, such as a sidewall or a rib, serving to prevent the movement of the material beyond the area from which transfer to the conveyor may be effected. Much of the material moving 0ut .of the open side of the machine in multi-pass mining tends to form windrows in the adjacent passageway beyond the reach of the cutter arms. A substantial quantity of mined material remains on the mine floor and is not gathered by the boring arms and fed to the conveyor on the mining ma chine. This requires a separate gathering means for the mined material left on the mine floor as a windrow.

Efforts have been previously made to attach a separate member adjacent the mining machine in order to provide the same barrier to material passage as the sidewall or rib provides in single-pass mining. In order to be effective, such a shield must extend the forwardmost point of the cutter arms. This being so, the member could be employed on the open side of the machine. It could not, however, remain on the machine during single-pass mining operations as the shield would engage the material face and prevent cutter contact with the face. One of the major weaknesses of such systems, is that the windrow shield or cleaner had to be removed from the machine prior to use of the machine for single pass mining.

SUMMARY OF THE INVENTION The mining machine of this invention provides permanently secured windrow cleaner or shield which may assume either a forward shielding position or a rear storage position. The windrow shield is adapted to be moved boring shaft. In this position, the shield extends further forward than the cutter arms. In addition, the shield is preferably curved concavely inward toward the cutter arms to facilitate return of the materials to a position which can be reached by the pusher plates of the cutter arms. When the shield is in its rear storage position, it is in a non-interfering position with respect to normal single-pass operation of the mining machine.

It is an object of this invention to provide a mining machine having a permanently secured windrow shield adapted to assume either a forward shielding position or a rear storage position.

It is another object of this invention to provide a mining machine windrow shield which is adapted to be locked in a forward shielding position and moved by means of a rotatably mounted supporting member to a non-interfering rear storage position.

It is yet another object of this invention to provide a windrow cleaner which is designed to effectively reduce windrow losses, while permitting rapid movement of the shield to and from its forward shielding position without extended cessation of the mining operation.

It is further object of this invention to provide such a windrow cleaner which is adapted for use with conventional mining equipment without major alteration to the machine structure or function.

Other objects and advantages of this invention will be understood from the following description of the invention, or reference to the illustrations appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a front elevation of a mining machine having a form of windrow shield contemplated by this invention, being employed in a multi-pass operation.

FIGURE 2 is a side elevation of a mining machine having a windrow shield, with the windrow shield being disposed in the forward shielding position.

FIGURE 3 is a plan view of the type of windrow shield shown in FIGURES l and 2, illustrating the movement of the windrow shield between the front and rear position.

FIGURE 4 is a partial sectional view through 44 of FIGURE 3 showing the windrow shield structure.

FIGURE 5 is a partial sectional view through 5-5 of FIGURE 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring more specifically to the drawings, FIGURES 1 and 2 illustrate a boring type mining machine. As is shown in FIGURE 2, the machine has a ground-contacting endless tread 2 which supports a sub frame 4. A support bracket 6 secured to sub-frame 4 carries hydraulic cylinder 8. The upper portion of hydraulic cylinder 8 is secured to and supports main frame 10 through cooperation with bracket 12. The main frame 10 has a motor 44 and a gear case 14 which extends forwardly of subframe 4.

Boring shafts 16, 18 (FIGURE 2) are journaled in gear case 14, extend lengthwise of sub-frame 4 and are spaced apart transversely of the sub frame 4. Boring shafts 16, 18 have several radially disposed cutter arms 20, 22. These arms 20, 22 are conventionally mounted for telescoping radial extension and retraction. Each cutter arm 20, 22 has cutter members 24 disposed substantially perpendicular to the cutter arms 20, 22 and extending forwardly therefrom. Pusher plates 26, 42 are disposed at what will be the leading edge of each cutter arm 20, 22 as it rotates.

In addition to the cutting effected by the cutter members 24 during rotation of boring shafts 16, 18, trimmer bars 28, 30 contribute to the cutting operation. These bars 28, 30 are adapted to remove the upper and lower triangular cusps of material (not shown) which would otherwise be left adjacent the overlapping circular paths of the cutter arms 20, 22. The trimmer bars 28, 30 have guides for receiving endless cutter chain 32. Suitable guide sprockets (not shown) are provided to define a path of movement for the cutter chain 32.

A conveyor opening is disposed at the front of gear case 14 above the lower trimmer bar 30, approximately at the transverse center of the gear case 14. An endless conveyor (not shown) is disposed within this opening 110 and conveys the mined material fed to the conveyor opening 110 upwardly and rearwardly longitudinally through the machine.

In FIGURE 1, the mining machine is shown in use in multi-pass mining. At the right side of the figure, is rib or sidewall 116 which is composed of the material being mined. The material 160 may be a chemical such as potash, for example, or any other material generally extracted from the earth by this type of machine. To the left side of the figure is open passageway 118 which represents a passageway established by a previous pass of the machine.

In operation of the mining machine, the machine is moved on endless treads 2 until the cutter members 24 of cutter arms 20, 22 engage the face of the material 160 to be mined. The material 160 is then cut from the face by rotation of boring shafts 16, 18 and movement of the endless cutter chain 32. A substantial portion of the cut material will drop onto the passageway floor 114. Pusher plates 25, 42 which are secured to the leading edge of rotating cutter arms 20, 22 respectively, move the cut material toward the conveyor opening 110 for ultimate withdrawal to the rear of the machine.

Boring shaft 18 is rotated in a clock-wise direction. Any material which is deflected outwardly transversely of this side of the machine will contact rib 116 and drop down to the passageway floor 114. From this position pusher plates 42 and boring arms 22 move the material transversely inwardly toward the conveyor opening 110 for removal.

Boring shaft 16 rotates in a counter clock-wise direction. In prior machines, not having windrow shield 48, material deflected transversely outwardly of the machine by cutter arms 20 of boring shaft 16 would move into open passageway 118 and form windrows therein. The material moving into open passageway 118 was beyond the reach of pusher plates 26 and therefore, would not be directed toward conveyor opening 110. This otherwise usable material was, therefore, not gathered by the boring arms of the mining machine.

As is illustrated in FIGURES 1 and 2, the windrow shield 48 of this invention, is designed to serve as a barrier against the movement of material into the open passageway 118. Any material impinging upon shield wall 50 will be delivered to the passageway floor 114 for ultimate removal by the conveyor (not shown). As is shown in FIGURES 2 and 4, the windrow shield 48 has shield wall 50 which is generally vertically disposed and has a smooth inner face 52 facing inwardly toward boring shaft 16 and an outer face 54. Secured to the outer face 54 are a plurality of spaced horizontally disposed reinforcing members 56. A plurality of spaced vertically disposed reinforcing members 58 are secured to the outer portions of horizontally disposed reinforcing members 56.

As is shown in FIGURE 4, the shield wall 50 is preferably curved and has a concave inner face 52 oriented toward boring shaft 16. The wall 50 extends from a bottom extremity 60 closely adjacent the passageway floor 114 to an upper extremity disposed higher than boring shaft 16. The wall 50 has a leading edge 64 and a rear edge 66.

In the forward shielding position, shield wall 50 is substantially parallel to boring shaft 16 and spaced therefrom a greater distance than the length of cutter arms 20. In this forward shielding position (FIGURE 2), the shield wall 50 extends further forward than cutter arms 20 and cutter members 24. This extension places the shield wall 50 in the adjacent passageway 118 and thus the cutter members 24 make contact with mine face 68 without interference from shield wall 50.

In the rear storage position, shield wall 50 is substantially parallel to boring shaft 16, but spaced therefrom a distance less than the length of cutter arms 24. It will be appreciated that in single-pass mining and in the initial pass in multi-pass mining, shield wall 50 could not be in the forward shielding position, as shown in FIGURE 2. This is so as the front edge 64 would contact mine face 68 and prevent the cutter members 24 from contacting the face 68. The shield wall 50 is, for this reason, while permanently secured to the side of gear case 14, adapted to be moved to a rear storage position. In this rear storage position, the shield wall 50 remains substantially vertical and parallel to boring shaft 16 but the leading edge 64 is disposed behind the rearmost edge of cutter arms 20. The shield wall 50 is, in this position, disposed closely adjacent the side of gear case 14 and is therefore, in a non-interfering position with respect to normal mining operation.

Shield wall 50 is provided with rear extensions 70, 72 as is shown in FIGURE 2. As is shown in FIGURE 4, secured, respectively, to these extensions 70, 72 are mounting brackets 74, 76. Mounting brackets 78, 80 are secured to the gear case 14. FIGURE 2 illustrates a rigid supporting member 120 which has a substantially rectangular configuration. Elongate top member 122 and elongate bottom member 124 are secured to opposed ends of side members 126, 128, which are spaced inwardly from the ends of top members 122, 124. For additional rigidity, cross supports 130, 132 are provided.

The ends of top member 122 and bottom member 124 are provided with openings which are adapted to be aligned with corresponding openings in mounting brackets 74, 76, 78, 80. As shown in FIGURE 4, the openings in support member 120 are aligned with the openings of brackets 74, 76, 78, 80 and rods 134, 136 are passed through the aligned openings. For clarity of illustration, cross supports 130, 132 of rigid supporting member 120 have not been shown in FIGURE 4. The rods 134, 136 have heads 138, 140, respectively, at their upper ends and are secured against removal by pins 142, 144, respectively, passing through openings at their lower ends. With the rods 134, 136 so positioned, rigid supporting frame is rotatably secured to both gear case 14 and shield wall 50. As shown in FIGURE 3, movement of shield wall 50 from the forward shielding position (shown in solid lines) to the rear storage position (shown in dotted lines) can be effected by rotating rigid supporting member 120 about rod 136 with rod 134 moving in the path indicated by the arrow.

In the form of support assembly selected for purposes of illustration, auxiliary support member 141 is provided for additional support. This support member 141 must be released before the shield wall 50 can be moved to the rear storage position. Auxiliary support member 141 is an elongate bar having openings adjacent each end. One end is secured to rear extension 70 of shield wall 50 by means of rod 134. The other end is secured within fork-shaped bracket 148 by means of pin 150. Bracket 148 is secured to gear case 14 and pin 150 is secured to retainer chain 152 which also is secured to gear case 14. Before shield wall 50 is moved from its forward shielding position, pin 150 is withdrawn from bracket 148 and that end of auxiliary support member 141 is thereby freed. Upon movement of the shield wall 50 to the forward shielding position, support member is placed within bracket 148 and pin 150 is reinserted in order to secure the support shield Wall 50.

It will be appreciated that even with the auxiliary support member 141 secured to gear case 14, a certain degree of free rearward movement of the shield wall 50 is possible. As such movement would produce undesirable stability in the windrow shield, locking means are provided in order to secure the shield wall immovably in the forward shielding position. The locking means has a rigid elongated locking member 100 which, as shown in FIGURE 3, has one end permanently secured to shield wall 50. This may conveniently be accomplished by securing rigid elongate locking member to one or more of the vertically disposed reinforcing members 158. The other end of locking member 100 has an extension 108 which is adapted to be received in fork-shaped mounting bracket 102. The details of this locking assembly are shown in FIGURE 5. An opening in extension member 108 of locking member 100 is adapted to be aligned with a pair of openings in bracket 102 when shield wall 50 is in the forward shielding position. A locking pin 104 is passed through the aligned openings to lock the shield wall in position. The locking pin 104 may be conveniently secured to gear case 14 by means of chain 106.

Referring now to FIGURE 3, it is seen that the solid lines illustrate the shield wall 50 in the forward shielding position. In this position, it is supported by rigid supporting member and auxiliary supporting member 141. It is locked in this position by elongate locking member 100 in cooperation with bracket 102 and locking pin 104. When it is desired to place the shield wall 50 in its rear storage position (indicated by the dotted lines in FIGURE 3) locking pin 104 and pin are removed. Support member 120 may then be rotated about rod 136 until shield wall 50 assumes the rear storage position and locking member assumes position 100'. If desired, locking means (not shown) may be provided in order to secure the shield wall 50 in the storage position.

It will be appreciated that this invention provides an effective windrow shield 48 which is permanently secured to the mining machine and is adapted to be placed simply and quickly in a rear storage position. The rear storage position is such that the windrow shield 48 does not interfere with normal single-pass mining operation. This is so as the shield 48 in storage position remains vertical and is disposed closely adjacent one side of gear case 14. In this position, its forward edge 57' terminates behind the cutter arms 20, 22. The stored shield wall 50' will not interfere with a side Wall or rib of a mine seam nor will it interfere with the efiecting of engagement between the cutter members 24 and the mine face. All of this is accomplished with a minimum of alteration of the structure and operation of the mining machine and while eliminating extended shut-down periods during positioning of the windrow shield 48.

While for purposes of simplicity of discussion a single windrow shield has been shown, it will be obvious that a pair of windrow shields may advantageously be secured to opposite sides of the mining machine. Such use of two shields on a single machine is contemplated by this invention.

While a preferred form of reinforced shield wall structure has been shown for purposes of illustration, it will be appreciated that a wall member made of a thicker gauge of material would require little or no reinforcement. Such structures are within the contemplation of this invention.

Whereas, particular embodiments of the invention have been described above for purposes of illustration, it will be apparent to those skilled in the art that numerous variations of the details may be made without departing from the appended claims.

I claim: 1. In a mining machine, ground engaging traction means, a subframe supported upon said traction means, a main frame mounted upon said subframe and having a gear case extending forwardly therefrom,

boring shafts journaled in said gear case extending lengthwise of said subframe and spaced apart transversely of said subframe,

radially disposed cutter arms on the forward ends of said boring shafts,

shielding means permanently secured to at least one side of said gear case having a substantially vertical shield wall, said shield wall being curved with a concave inner shielding surface facing said boring shaft and an outer surface,

support means rotatably connecting said shield wall to said gear case side,

said shield wall adapted to assume a forward shielding position substantially parallel to one boring shaft and spaced therefrom a distance greater than the length of said cutter arms and extending further forward than said cutter arms,

said shield wall adapted to assume a rear storage position closely adjacent said gear case side and extending rearwardly of said cutter arms, said shield wall in said rear storage position being spaced from said boring shaft a distance less than the length of said cutter arms,

locking means to secure said shield wall in said forward shielding position and including a substantially horizontally disposed rigid elongate locking member with one end permanently secured to said shield wall and another end demountably secured to said gear case side by fastening means having a locked position and an unlocked position whereby movement of said shield wall from said forward shielding position to said rear storage position can be effected only when said fastening means is in an unlocked position,

a plurality of spaced horizontally disposed reinforcing members secured to said outer face of said shield wall,

a plurality of spaced vertically disposed reinforcing members secured to said horizontally disposed reinforcing members, and

one end of said rigid locking member permanently secured to at least one of said vertically disposed reinforcing members.

2. The mining machine of claim 1, wherein,

shielding means are provided on each side of said gear case.

3. The mining machine of claim 1, wherein,

said shield Wall has a lower end disposed closely adjacent the ground and an upper disposed at a higher elevation than said boring shaft.

4. The mining machine of claim 3 including,

auxiliary support means detachably connecting said upper end of said shield wall with said gear case side when said shield wall is in said forward shielding position.

5. The mining machine of claim 4 wherein,

said auxiliary support means has a supporting arm with one end rotatably secured to said upper end of said shield wall and the other end detachably secured to said gear case side.

References Cited UNITED STATES PATENTS 2,734,731 2/ 1956 Cartlidge et al 299--57 2,740,618 4/1956 Snyder et a1. 29957 2,753,971 7/1956 Ball 1989 X 3,190,697 6/ 1965 Gonski 29964 ERNEST R. PURSER, Primary Examiner U.S. Cl. X.R. 

